Kale Pineapple Drink Kale is a popular vegetable and a member of the cabbage family. It is a cruciferous vegetable like cabbage, broccoli, cauliflower, collard greens and Brussels sprouts. There are many different types of kale. The leaves can be green or purple, and have either a smooth or curly shape. The most common type of kale is called curly kale or Scots kale, which has green and curly leaves and a hard, fibrous stem.